Immunodeficiency Disorders: Causes, Mechanisms, and Clinical Manifestations

Question 1

Which clinical feature is characteristic of Bruton's agammaglobulinemia?

Accepted Answer

Frequent bacterial infections

Answer

Autoimmune disorders

Answer

Increased eosinophils

Question 2

Which of the following is NOT a commonly encountered cause of primary immunodeficiencies?

Accepted Answer

Presence of autoimmune diseases

Answer

Genetic mutations or deletions

Answer

Prenatal exposure to infections

Answer

Environmental exposures

Question 3

Which type of immunodeficiency is primarily characterized by impaired antibody production?

Accepted Answer

B-cell deficiency

Answer

T-cell deficiency

Answer

Combined immunodeficiency

Answer

Phagocytic immunodeficiency

Question 4

Which of the following complications is commonly observed in neonates with severe combined immunodeficiency (SCID)?

Accepted Answer

Pneumocystis jirovecii pneumonia (PCP)

Answer

Graft-versus-host disease (GvHD)

Answer

Epstein-Barr virus (EBV) infection

Answer

Human cytomegalovirus (HCMV) infection

Question 5

Which type of acquired immunodeficiency is caused by infection with the human immunodeficiency virus (HIV)?

Accepted Answer

Cellular immunodeficiency

Answer

Humoral immunodeficiency

Answer

Combined immunodeficiency

Answer

Phagocytic immunodeficiency

Question 6

Which clinical manifestation is characteristic of X-linked agammaglobulinemia?

Accepted Answer

Recurrent bacterial infections

Answer

Autoimmune disorders

Answer

Eosinophilia

Answer

Neutropenia

Question 7

Which of the following is a defining characteristic of primary immunodeficiencies?

Accepted Answer

Underlying genetic etiology

Answer

Onset typically in adulthood

Answer

Development following exposure to environmental factors

Answer

Association with underlying systemic disorders

Question 8

Deficiencies in which immune cell type are primarily responsible for severe combined immunodeficiency (SCID)?

Accepted Answer

T and B lymphocytes

Answer

Neutrophils

Answer

Natural killer cells

Answer

Macrophages

Question 9

Which of the following molecular mechanisms plays a central role in HIV-induced immunodeficiency?

Accepted Answer

Progressive depletion of CD4+ T cells

Answer

Impairment of antigen presentation by MHC class II molecules

Answer

Dysregulation of cytokine production

Answer

Downregulation of complement proteins

Question 10

Immunosuppressive medications are used to prevent rejection following organ transplantation. What is the primary target of immunosuppressive therapy?

Accepted Answer

T lymphocytes

Answer

B lymphocytes

Answer

Neutrophils

Answer

Macrophages

Question 11

Which laboratory test is most valuable for evaluating humoral immunity?

Accepted Answer

Serum immunoglobulin levels

Answer

Complete blood count

Answer

Flow cytometry analysis of lymphocyte subsets

Answer

Nitroblue tetrazolium test

Question 12

Which of the following is a defining characteristic of primary immunodeficiencies?

Accepted Answer

Genetic basis

Answer

Onset typically in adulthood

Answer

Acquired after birth

Answer

Caused predominantly by environmental factors

Question 13

Which statement about acquired immunodeficiencies is accurate?

Accepted Answer

They can develop at any age

Answer

They are exclusively caused by infectious agents

Answer

They predominantly affect cell-mediated immunity

Answer

They are typically inherited disorders

Question 14

Which diagnostic test is used to evaluate the integrity of the humoral immune system?

Accepted Answer

Serum immunoglobulin levels

Answer

T-cell proliferation assay

Answer

Skin prick test

Answer

Flow cytometry

Question 15

Which of the following is an acquired immunodeficiency disorder?

Accepted Answer

HIV/AIDS

Answer

Common variable immunodeficiency (CVID)

Answer

Severe combined immunodeficiency (SCID)

Answer

X-linked agammaglobulinemia

Question 16

What is the primary function of Bruton's tyrosine kinase (BTK) in B cells?

Accepted Answer

Phosphorylates the cytoplasmic tail of the B cell receptor (BCR)

Answer

Promotes the differentiation of myeloid cells

Answer

Inhibits the activation of T cells

Question 17

Which clinical manifestation is characteristic of severe combined immunodeficiency (SCID)?

Accepted Answer

Recurrent infections with opportunistic organisms

Answer

Allergies

Answer

Autoimmune disorders

Answer

Delayed puberty

Question 18

Which is a potential complication of immunoglobulin replacement therapy for immunodeficiency?

Accepted Answer

Anaphylaxis

Answer

Hemolytic anemia

Answer

Thrombocytopenia

Answer

Pneumonia

Question 19

What is the primary causative agent of acquired immunodeficiency syndrome (AIDS)?

Accepted Answer

Infection with human immunodeficiency virus (HIV)

Answer

Autoimmune disorders

Answer

Defects in antibody production

Answer

Loss of T cell function

Question 20

Which of the following is a common opportunistic infection associated with AIDS?

Accepted Answer

Pneumocystis jirovecii pneumonia

Answer

Chickenpox

Answer

Influenza

Answer

Malaria

Question 21

How is the diagnosis of AIDS typically established?

Accepted Answer

Detection of HIV antibodies and a CD4 count below 200 cells/μL

Answer

Positive skin test to tuberculosis antigen

Answer

Elevated serum immunoglobulin levels

Question 22

Which of the following is a treatment option for AIDS?

Accepted Answer

Antiretroviral therapy

Answer

Surgery

Answer

Immunoglobulin replacement therapy

Answer

Stem cell transplantation

Question 23

What is the primary objective of treating immunodeficiency disorders?

Accepted Answer

To restore or enhance immune function

Answer

To prevent infections

Answer

To suppress inflammation

Answer

To correct genetic defects